Laravel 10 Many to Many Eloquent Relationship Tutorial

Laravel 10, many-to-many relationships where condition and everything related to many to many relationship.

In this example, i will create "users", "roles" and "role_user" tables. each table is connected with each other. now we will create many to many relationships with each other by using the laravel Eloquent Model. We will first create database migration, then model, retrieve records and then how to create records too.

Create Migrations:

users table migration: 

<?php
  
    use Illuminate\Database\Migrations\Migration;
    use Illuminate\Database\Schema\Blueprint;
    use Illuminate\Support\Facades\Schema;
      
    return new class extends Migration
    {
        /**
         * Run the migrations.
         *
         * @return void
         */
        public function up(): void
        {
            Schema::create('users', function (Blueprint $table) {
                $table->id();
                $table->string('name');
                $table->string('email')->unique();
                $table->timestamp('email_verified_at')->nullable();
                $table->string('password');
                $table->rememberToken();
                $table->timestamps();
            });
        }
        /**
         * Reverse the migrations.
         *
         * @return void
         */
        public function down(): void
        {
            Schema::dropIfExists('users');
        }
    };

roles table migration:

<?php
  
    use Illuminate\Database\Migrations\Migration;
    use Illuminate\Database\Schema\Blueprint;
    use Illuminate\Support\Facades\Schema;
      
    return new class extends Migration
    {
        /**
         * Run the migrations.
         *
         * @return void
         */
        public function up(): void
        {
            Schema::create('roles', function (Blueprint $table) {
                $table->id();
                $table->string('name');
                $table->timestamps();
            });
        }
      
        /**
         * Reverse the migrations.
         *
         * @return void
         */
        public function down(): void
        {
            Schema::dropIfExists('roles');
        }
    };

role_user table migration:

<?php
  
    use Illuminate\Database\Migrations\Migration;
    use Illuminate\Database\Schema\Blueprint;
    use Illuminate\Support\Facades\Schema;
      
    return new class extends Migration
    {
        /**
         * Run the migrations.
         *
         * @return void
         */
        public function up(): void
        {
            Schema::create('role_user', function (Blueprint $table) {
                $table->foreignId('user_id')->constrained('users');
                $table->foreignId('role_id')->constrained('roles');
            });
        }
        /**
         * Reverse the migrations.
         *
         * @return void
         */
        public function down(): void
        {   
            Schema::dropIfExists('role_user');
        }

Create Models:

User Model:

<?php
  
    namespace App\Models;
      
    use Illuminate\Contracts\Auth\MustVerifyEmail;
    use Illuminate\Database\Eloquent\Factories\HasFactory;
    use Illuminate\Foundation\Auth\User as Authenticatable;
    use Illuminate\Notifications\Notifiable;
    use Laravel\Sanctum\HasApiTokens;
    use Illuminate\Database\Eloquent\Relations\BelongsToMany;
      
    class User extends Authenticatable
    {
        use HasApiTokens, HasFactory, Notifiable;
      
        /**
         * The attributes that are mass assignable.
         *
         * @var array
    
         */
        protected $fillable = [
            'name',
            'email',
            'password',
        ];
      
        /**
         * The attributes that should be hidden for serialization.
         *
         * @var array
    
         */
        protected $hidden = [
            'password',
            'remember_token',
        ];
      
        /**
         * The attributes that should be cast.
         *
         * @var array
    
         */
        protected $casts = [
            'email_verified_at' => 'datetime',
        ];
      
        /**
         * The roles that belong to the user.
         */
        public function roles(): BelongsToMany
        {
            return $this->belongsToMany(Role::class, 'role_user');
        }
    }

Role Model:

<?php
  
    namespace App\Models;
      
    use Illuminate\Database\Eloquent\Factories\HasFactory;
    use Illuminate\Database\Eloquent\Model;
    use Illuminate\Database\Eloquent\Relations\BelongsToMany;
      
    class Role extends Model
    {
        use HasFactory;
      
        /**
         * The users that belong to the role.
         */
        public function users(): BelongsToMany
        {
            return $this->belongsToMany(User::class, 'role_user');
        }
    }

UserRole Model:

<?php
  
    namespace App\Models;
      
    use Illuminate\Database\Eloquent\Factories\HasFactory;
    use Illuminate\Database\Eloquent\Model;
      
    class UserRole extends Model
    {
        use HasFactory;
          
    }

Retrieve Records:

$user = User::find(1);  
 dd($user->roles);

$role = Role::find(1);  
 dd($role->users);

Create Records:

$user = User::find(2);  
    $roleIds = [1, 2];
    $user->roles()->attach($roleIds);

$user = User::find(3);  
    $roleIds = [1, 2];
    $user->roles()->sync($roleIds);

$role = Role::find(1);  
    $userIds = [10, 11];
    $role->users()->attach($userIds);

$role = Role::find(2);  
    $userIds = [10, 11];
    $role->users()->sync($userIds);